en ميکروب شناسي Microbiology Research Article Research Article <span style="font-size:12pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times=""><span style="color:black"><b>Abstract </b></span></span></span></span><br> <span style="font-size:12pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times=""><span style="color:black"><b>Background:</b> Biofilm formation in&nbsp;<i>Staphylococcus aureus </i>(<i>S. aureus</i>), mediated by the&nbsp;<i>ica</i>&nbsp;operon, is a key virulence factor. This study examined how different glucose-supplemented broth culture media influence biofilm production and&nbsp;<i>ica</i>&nbsp;gene expression in&nbsp;<i>S. aureus</i>.</span></span></span></span><br> <span style="font-size:12pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times=""><span style="color:black"><b>Methods:</b> The phenotypic ability to adhere to a polystyrene surface and to produce slime layer were evaluated using <span style="line-height:200%">microtiter plate test (</span>MtP) and Congo red tube test, respectively. Using PCR, the presence of intercellular adhesion (<i>ica</i>) locus<i> </i>in <i>S. aureus</i> strains was confirmed and subsequently, quantitative real-time RT-PCR was performed to investigate transcription of <i>icaA</i> in various media including Tryptic soy broth (TSB), Brain-heart infusion broth (BHIB), (Nutrient broth) NB and (Muller-Hinton broth) MHB contained 0, 0.25, 0.5, 1 and 2% glucose.</span></span></span></span><br> <span style="font-size:12pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times=""><span style="color:black"><b>Results:</b> Our results showed that although all of the studied strains adhered to the wells of polystyrene microtiter plates, the optimum rate of biofilm formation was observed for TSB medium contained 1% glucose, but biofilm formation was not significantly different in NB, MHB and BHIB media. Supplementation of all media with 1% glucose led to the highest production of biofilm formation and in all media transcription of <i>icaA</i> was increased with glucose addition to one present.</span></span></span></span><br> <b><span lang="EN-GB" style="font-size:11.0pt"><span style="line-height:115%"><span calibri="" style="font-family:">Conclusions:</span></span></span></b> <span lang="TR" style="font-size:11.0pt"><span style="line-height:115%"><span calibri="" style="font-family:">The results of the present study indicated that TSB medium supplemented with 1% glucose was the most appropriate medium for evaluation of biofilm formation by <i>S. aureus</i> isolates.</span></span></span> Biofilm formation, Staphylococcus aureus, Culture media, glucose, quantitative real-time RT-PCR 0 0 http://mlj.goums.ac.ir/browse.php?a_code=A-10-1738-1&slc_lang=en&sid=1 Aram Sharifi a.sharifi@uok.ac.ir 100319475328460032405 100319475328460032405 No Department of Animal Science, Faculty of Agriculture, University of Kurdistan, Sanandaj, Kurdistan, Iran Abdolmajid Mohammadzadeh Mohammadzadeh@basu.ac.ir 100319475328460032406 100319475328460032406 Yes Department of Pathobiology, Faculty of Veterinary Science, Bu-Ali Sina University, Hamedan, Iran Pezhman Mahmoodi mahmoodi_pezhman@yahoo.com 100319475328460032407 100319475328460032407 No Department of Pathobiology, Faculty of Veterinary Science, Bu-Ali Sina University, Hamedan, Iran Taghi Zahraei Salehi tsalehi@ut.ac.ir 100319475328460032408 100319475328460032408 No Department of Microbiology and Immunology, Faculty of Veterinary Science, Tehran University, Tehran, Iran